4-arylaminopyridine herbicides

ABSTRACT

A herbicidal and pesticidal composition comprising an arylaminopyridine of the formula:   OR A SALT THEREOF, WHEREIN R represents a hydrogen atom, an acyl radical or a hydrocarbyl radical; Ar represents an aryl radical optionally substituted by one or more chlorine, bromine, fluorine, nitro, cyano, perhalocarbyl sulphamoyl hydrocarbyl hydrocarbyloxy, or hydrocarbylthio radicals; X represents a chlorine, bromine, fluorine, nitro, cyano, hydrocarbyloxy or hydrocarbylthio radical; and n is 3 or 4; and a carrier therefor.

nited States Patent 1191 Tomlin et al.

[ 1 Dec. 16, 1975 4-ARYLAMINOPYRIDINE HERBICIDES {75] Inventors: Clive Dudley Spencer Tomlin,

[73] Assignee: Imperial Chemical Industries Limited, London, England 221 Filed: Feb.29, 1972 21 Appl. No.: 230,514

[30] Foreign Application Priority Data Mar. 19, 1971 United Kingdom 7291/71 [52] US. Cl. 71/94; 424/263; 260/293.87 [51] Int. Cl. AOIN 9/22 [58] Field of Search 71/94; 260/296 R [56] References Cited UNITED STATES PATENTS 3,317,542 5/1967 l-Iaszeldine et a1 71/94 X 3,495,969 2/1970 Driscoll 3,545,955 12/1970 George et a1. 3,547,935 12/1970 Diehl et al. 260/927 3,576,616 4/1971 Nowotny 71/94 3,641,042 2/1972 Ayad 1. 260/296 R 3,686,230 8/1972 Maravetz 260/347.7 3,838,159 9/1974 Johnston 71/94 X OTHER PUBLICATIONS Ivashchenko et a1., Khim. Geterotsikl, Soedin, 1970,

(7), 963-965, (Russ), Chem. Abst. Vol. 75, (1971), 48847g.

Primary ExaminerLewis Gotts Assistant Examiner-Catherine L. Mills Attorney, Agent, or Firm-Cushman, Darby & Cushman [57] ABSTRACT A herbicidal and pesticidal composition comprising an arylaminopyridine of the formula:

or a salt thereof, wherein R represents a hydrogen atom, an acyl radical or a hydrocarbyl radical; Ar represents an aryl radical optionally substituted by one or more chlorine, bromine, fluorine, nitro, cyano, perhalocarbyl sulphamoyl hydrocarbyl hydrocarbyloxy, or hydrocarbylthio radicals; X represents a chlorine, bromine, fluorine, nitro, cyano, hydrocarbyloxy or hydrocarbylthio radical; and n is, 3 or 4; and a carrier therefor.

3 Claims, No Drawings .1 4-ARYLAMINOPYRIDINE HERBICIDES or a salt thereof, wherein R represents a hydrogen atom, an acyl radical, or a hydrocarbyl radical; Ar represents an aryl radical optionally substituted by one or more chlorine, bromine, fluorine nitro, cyano, perhalocarbyl sulphamoyl, hydrocarbyl, hydrocarbyloxy, or hydrocarbylthio radicals; X represents a chlorine, bromine, fluorine, nitro, cyano, hydrocarbyloxy or hydrocarbylthio radical; and n is 3 or 4; in admixture with a solid diluent or a liquid diluent containing a surface-active agent. Preferred hydrocarbyl radicals are alkyl groups of l to 4 carbon atoms. Examples of preferred perhalocarbyl radicals include the trifluoromethyl radical. Examples of preferred hydrocarbyloxy groups include alkoxy radicals of l to 4;carbon atoms. Examples of preferred hydrocarbylthioradicals include alkylthio radicals ofl to 4 carbon atoms.

Preferred compounds as active ingredients are those in which the aryl radical is a substituted phenyl or naphthyl radical. Y

Preferably the bondbetween the pyridine ring and the group in the foregoing formula is located at the 4- position of the pyridine ring. Particularly preferred compounds as active ingredients are those in which the group R represents a hydrogen atom. Preferred compounds for use as active ingredients include those in which each group X is a fluorine or chlorine atom and n is 4. Where the group R represents an acyl group, the acyl group may for example be derived from a carboxylic acid; for example it may be an alkanoyl group of from 2 to 5 carbon atoms. The acyl group may also be a carbomoyl group, for example a carbamoyl group bearing one or two alkyl substituents each of l to 4 carbon atoms. Where R represents a hydrocarbyl group, it may be for example an alkyl group of from 1 to 5 carbon atoms. Preferably the aryl group Ar bears a nitro,cyano or trifluoromethyl substituent. The term salt is' intended to include both salts formed from reaction of the com-.

pounds of the foregoingformula with bases, for example salts formed from metal cations and ammonium cations, and salts formed by reaction of compounds of the foregoing formula with acids.

Particular examples of compounds useful as active ingredients of the compositions of the invention are listed in Tablel below.

TABLE: I

Compound Structural Formula Mehmg poim No. 0

; cl 7 Cl F ct TABLE l-Cominued TABLE l-Continued Compound SHUC'UmI Formula Mowing poi-6' :omptw'nd Structural Formula lyi point i O. No. C 0C Cl c| F G 114 -s 49 M NH NO 170-7- 10 I '3 115-7 F Br (or 2 isomer) 1 C] F F F Cl Br 42 N NH N 2 50 N/ No 55 Cl Cl F F F c F ci (:1 F

H 1 0M 2 01 ca i F F m i221? n a 0 F c1 F F The formulae given In Table I above are believed to be those which correspond most closely to the molecular structure of the compounds. However, a compound 5 N 4 N 2 iaaizof the formula: i

F c1 F F CONHCH F Cl 46 N CN 205.5

cH O C] F is, in principle, capable of existing in different tautocomma meric forms such, as for example the following N 47 NH NO 126-s- In 2 127.7 I C c] EN N-Ar and 48 naa The formulaeglven'ln Table I above are to be consldered as representativeiof and including all such tautomeric forms.

Compositions according to the invention may be in active ingredient is mixed with a solid diluent or carrier. Suitable solid diluents or carriers may be, for example kaolinite (china clay), montmorillonite, attapulgite, talc, pumice, silica, calcium carbonate, gypsum, powdered magnesia, Fullers earth, and diatomaceous earth. Compositions for dressing seed, for example, may comprise an agent assisting the adhesion of the composition of the seed, for example a mineral oil.

The composition may also be in the form of dispersible powders or grains comprising, in addition to the active ingredient, a wetting agent to facilitate the dispersion of the powder or grains in liquids. Such powders or grains may include fillers, suspending agents and the like.

The compositions may also be in the form of liquid preparations to be used as dips or sprays which are generally aqueous dispersions or emulsions containing the active ingredient in' the presence of one or more wetting agents, dispersingagents, emulsifying agents or suspending agents. i V

Wetting agents, dispersing agents and emulsifying agents may be of the cationic, anionic, or non-ionic type. Suitable agents of the cationic type include, for example, quaternary ammonium compounds, for example cetyltrimethylammonium bromide. Suitable agents of the'anionic type include, for example, soaps, salts of aliphatic monoest'er's'of sulphuric acid, for example sodium lauryl sulphate, salts "of sulphonated aromatic compounds, for exarnple sodium dodecylbenzenesulphonate, sodium, calcium or ammonium lignosulphonate, butylnaphthalene sulphonate, and a mixture of the sodium salts of diisopropyland triisopropylnaphthalene sulphonic acids.

Suitable agents of the non-ionic type include, for

example, the condensation products of ethylene oxide with fatty alcohols such as oleyl alcohol or cetyl alcohol, or with alkyl phenols such as octylphenol, nonylphenol and octylcresol. Other non-ionic agents are the partial esters derived from long chain fatty acids and hexitol anhydrides, the condensation products of the said partial esters with ethylene oxide, the lecithins, and block copolymers of ethylene oxide and propylene oxide.

Suitable suspending agents are, for example bentonite, pyrogenic silica, and hydrophilic colloids, for example polyvinylpyrrolidone and sodium carboxymethylcellulose, and the vegetable gums, for example gum acacia and gum tragacanth.

The aqueous solutions dispersions or emulsions may be prepared by dissolving the active ingredient or ingredients in an organic solvent which may contain one or more wetting, dispersing or emulsifying agents and then adding the mixture so obtained to water which may likewise contain one or more wetting, dispersing or emulsifying agents. Suitable organic solvents are ethylene dichloride, isopropyl alcohol, xylenes and trichloroethylene. Concentrated solutions of the active ingredient in an organic solvent containing a dispersing agent to facilitate the dispersion of the organic solvent to form an emulsion when mixed with water are known as emulsifiable concentrates.

The compounds of the invention may also be formulated into compositions comprising capsules or microcapsules containing either the active ingredient itself, or a compositioncontainin g the active ingredient, and

prepared by any of the known encapsulation or microencapsulation techniques.

The compositions to be used as sprays may also be in the form of aerosols wherein the formulation is held in a container under pressure in the presence of a propellant such as fluorotrichloromethane or dichlorodifiuoromethane. j t

The compositions which are to be used in the fonn of aqueous dispersions or emulsions are generally supplied in the form of a concentrate containing a high proportion of the'active ingredient or ingredients, the said concentrate to be diluted with water before use.

These concentrates are often required to withstand storage for prolonged periods and after such storage, to be capable of dilution withwater in order to form aqueous preparations which remain homogeneous for a sufficient time to enable them to be applied by conventional spray equipment. The concentrates may conveniently contain from 10 '85% by weight of the active ingredient or ingredients and generally from 25 60% by weight of the active ingredient or ingredients. When diluted to form aqueous preparations, such preparations may contain varying amounts of the active ingredient or ingredients depending upon the purpose for which they are to be used, but an aqueous preparation containing between 0.000 1 and 1.0% by weight of the active ingredient or ingredients may be used.

The arylaminopyridine derivatives specified hereinbefore as active ingredients of the compositions of the invention are toxic towards a wide variety of pests, including the following Tetranychus telarius Aphis fabae Megoura viciae Aedes aegypti Musca domestica Pieris brassicae Plutella maculipennis Phaedon cochleariae Meloidogyne incognita Agriolimax reticulatus Calandra granaria The term pests is intended to include fungal pathogens of plants and seeds including for example, the following (brown rust on wheat) (late blight on tomatoes) (downy mildew on vines) (powdery mildew on vines) (blast on rice) (powdery mildew on" apples) (apple scab) Puccinia recondita Phytophthora infestans PIasmopara-viticola Uncinula necator Piricularia oryzae Podosphaera leucotricha Venturiainaequalis Certain of the compounds show algicidal properties.

The arylaminopyridine compounds are also toxic towards bacteria which cause bacterial diseases of plants, for example the following Comm-on name Crown gall of vegetables Canker of tomatoes Blackarm of cotton Soft rot of vegetables Rice bllight' Dieback of beans, stone fruit Potato scab Canker of stone fruit Halo'blight of beans Fire blight of pear and apple Bacterium Agrobacterium tumifaciens Corynebacterium michiganense Xanthomonas malvacearum Erwinia carotovora Xanthomon as oryzae Pseudomonas syringae Streptomyces scabies Pseudomonas mors prunum Pseudomonas phaseolicola Erwinia am ylovora Fungus Host Crop Name Botrytis tulipae Bulbs Fire Nigrospora sphaerica Bananas Squirter Phomopsis citri Citrus Scab Alternaria citri Citrus Stem end rot Penicillium digitatum Citrus Green mould Gloeosporium musarum Bananas Blackend Fusarium caeruleum Potato Dry rot Ceratocystis paradoxa Sugar cane. Pineapple disease pineapple Phoma exigua Potato Gangrene Phytophthora citrophthora Citrus Grey mould Botryodiplodia theobromae Bananas Black end Citrus Stem end rot Diplodia natalensis wherein X, R, Ar and n are as hereinbefore defined, or a composition according to the invention.

In a further aspect, the invention provides a method of treating plants to render them less susceptible to damage by pests, which comprises applying to the plants, or to the seeds, corms, bulbs, tubers, rhizomes, or other propagative parts of the plants, a nonphytotoxic but pesticidally effective amount of an arylaminopyridine of the formula or a salt thereof, wherein X, Ar, R and n are as hereinbefore defined.

The invention additionally provides a method of inhibiting the growth of unwanted vegetation, which comprises applying to the vegetation, or to the locus of the vegetation or of seeds thereof, a herbicidally effective amount of an arylaminopyridine compound of the formula:

wherein X, Ar, R and n are as hereinbefore defined. The amount of arylaminopyridine compound used to inhibit the growth of vegetation will depend upon the particular compound chosen as well as on the identity of the vegetation, but in general an amount of from 0.22 to l 1.2 kilograms per hectare (0.2 to pounds per acre) is suitable.

In another aspect the invention arylaminopyridines of the formula:

provides NR Ar wherein R represents a hydrogen atom, an acyl radical, or a hydrocarbyl radical; Ar represents an aryl radical optionally substituted by one or more chlorine, bromine, fluorine, nitro, cyano, perhalocarbyl, sulphamoyl, hydrocarbyl, hydrocarbyloxy, or hydrocarbylthio radicals; X represents a chlorine, bromine, fluorine, nitro, cyano, hydrocarbyloxy, or hydrocarbylthio radical, and n is 3 or 4, provided that when X is Cl and n is 4, the aryl radical contains at least two substituents.

Preferred compounds according to the invention are those of the formula above wherein Ar is a substituted phenyl or naphthyl radical. Especially preferred compounds are those in which the group is linked to the 4 position of the pyridine ring. Further preferred compounds are those in which R is a hydrogen atom. Particularly preferred compounds are those in which each group X represents a fluorine or chlorine atom and n is 4.

The arylaminopyridine compounds of the last foregoing formula may conveniently be prepared by a process wherein an aminopyridine is reacted with a base and with an aryl halide Ar Hal according to the following reaction scheme;

NHR

Xn 4- base Alternatively an arylamino compound ArNl-lR may be reacted with a base and with a halogenopyridine according to the following reaction scheme:

ArNl-IR 4- base In the above reaction schemes, the symbol Hal stands for halogen, while the symbols X, R, Ar and n have the meanings previously assigned to them. An example of a base for use in the reaction is sodium hydride. Preferably the reaction is conducted in an inert diluent or solvent. Preferred solvents are aprotic dipolar solvents, for example dimethyl formamide.

Compounds having the formula:

F Cl

which may itself be prepared by treatment of the known compound with a methanolic solution of sodium methoxide.

The following Examples illustrate the invention.

EXAMPLE 1 This Example illustrates the fungicidal properties of compounds used as active ingredients in the compositions of the invention. The compounds were tested against a wide variety of foliar fungal diseases of plants. In the test, a composition comprising an aqueous solution or suspension of the test compound was sprayed on to the foliage or uninfected plants; the soil in which the plants were growing was also drenched with the composition. The compositions used for spraying and drencing contained 100 parts per million (ppm.) of the test compound except where otherwise stated in the table of results below. After spraying and drenching, the plants were then exposed to infection with the dis eases it was desired to control, along with control plants not treated with the compound. After a period of days, depending upon the particular disease, the extent of the disease was visually assessed, as a percentage of the disease established upon the control plants which had not been treated with the compound under test, according to the grading scheme below Grading Amount of disease as a percentage of disease on control plants 0 61 to l 26 to 60 2 6 to 25 3 i O to 5 In Table 2 below the names of the disease is given in the first column, and in the second column is given the time which elapsed between exposing the plants to infection and assessing the amount of disease. Table 3 gives the test results.

TABLE 2 Disease and Time interval Disease code Plant (days) letter Puccinia recondita (wheat) l0 A Phytophthora infestans (tomato) 3 B Plasmopara viticola (vine) l0 C Uncinula necator (vine) 10 D Piricularia oryzae (rice) 7 E Podosphaera leucotricha (apple) 7 F Venturia inaequalis (apple) 21 G Botrytis cinerea (chocolate spot of beans 3 H TABLE 3 Compound No. Disease code letter (Table 2) (Table l) A B C D E F G H *8 0 3 3 O O 9 3 0 0 3 3 2 l2 2 3 3 O 3 3 I3 0 3 0 2 0 2 l5 2 3 3 3 l6 0 O 3 O 0 2 0 l7 0 l 3 0 0 3 A dash means that no test was perfonned These compounds were applied at a rate of 50 ppm. spray combined with a 200 ppm soil drench.

Table 4 below gives the results of tests with some further compounds listed in Table 1.

TABLE 4 Compound No. Disease code Letter (Table 2) TABLE 4 cominued The results of the test-are given in Table 5 below. Compound No. Disease code Letter (Table 2) TABLE 5 (Table I) A B c E F H Compound No. Grading (see Table l) 26 P 3 3 P 3 3 4 3 27 0 P 3 3 P 3 3 5 3 6 3 28 0 P 3 3 P 3 3 9 2 10 3 29 P P 3 3 P 3 3 12 3 1O 14 3 30 0 l 3 O O 3 17 2 19 2 31 2 0 3 3 0 3 33 2 3 3 2 3 3 EXAMPLE 3 34 P 3 3 3 P 3 This Example illustrates the activity of compounds 35 2 3 3 0 2 O 0 used as active ingredients in compositions according to the invention as toxicants for a variety of insect and 36 2 2 3 O I 2 0 other pests. The compounds were used in the form of a 37 o 3 3 p 0 p liquid preparation containing 0.1% by weight of the compound, except in the tests with Aedes aegypti and 38 1 P 3 3 2 3 3 Meloza'ogyne zncogmta, where the preparations con- 39 l 2 3 0 l 0 3 tained 0.01% by weight of the compound. The prepara- 40 O P 3 3 l 3 2 trons were made by dissolving each of the compounds in a mlxture of solvents consisting of 4 parts by volume 41 0 P 3 3 P 3 3 of acetone and 1 part by volume of diacetone alcohol. 42 3 p p p 0 3 The solutions were then diluted with water containing 0.01% by weight of a wetting agent sold under the trade 43 P P 3 P 3 name LISSAPOL NX until the liquid preparations 44 2 -P 3 3 0 3 contained the required concentration of the com- The symbol P means that the compound was to phytotoxic for an assessment of disease control to be made. For the test on apple scab (G) a concentrationof 25 ppm was used.

EXAMPLE 2 This Example illustrates the algicidal activity of compounds used as active ingredients of compositions according to the invention. In a test for algicidal activity, a mixed culture of green algae in water (1 ml.) was made up to 5 ml. in a glass tube with an aqueous suspension or solution of the compound under test containing sufficient compound to bring the concentration to 20 parts per million of test compound, together with nutrients tosupport the growth of the algae. After 1 week the intensity of greening in the glass tubes was compared with untreated control cultures of algae, and the amount of algal growth assessed on a scale of 0 to 3, according to the grading scheme below:

pound. LISSAPOL is a registered Trade Mark.

The test procedure adopted with regard to each pest was basically the same and comprised supporting a number of the pests on a medium which was usually a host plant or a foodstuff on which the pests feed and treating either or both the pests and the medium with the preparations.

The mortality of the pests was then assessed at periods usually varying from one to three days after the treatment.

The results of the tests are given below in Table 6. In this table the first column indicates the name of the pest species. The subsequent columns indicate the host plant or medium on which it was supported, the number of days which were allowed to elapse after the treatment before assessing the mortality of the pests, and the results obtained for each of the compounds, numbered as in Table 1 above. The assessment is expressed in integers which range from 0 to 3.

0 represents less than 30% kill.

1 represents 30 49% kill.

Grading Algal growth a 0f 2 represents kill. 0 g g if 3 represents over 90% kill. 1 25 to 60 55 C indicates a chemosterilant effect. 3 8:: g A indicates an antifeeding effect.

A dash in Table 6 indicates that no test was carried out.

TABLE 6 No. 3 Support of No. of Compound (Table l) Pest Species medium days 1 2 4 5 8 9 10 ll l2 l3 l5 l6 l8 19 20 21 22 Tetranychus telarius French (redspidermites, Bean i 3 3 3 0 3 3 3 3 0 3 0 3 2 0 3 3 3 0 adults) C C Tetranychus telarius French (redspidermites, Bean 3 0 0 0 3 3 0 3 0 2 0 2 3 3 3 0 eggs) Aphis fabae Broad TABLE 6-continued No. Support of No. of Compound (Table l) PestSpecies medium days l 2 3 4 5 8 9 l ll l2 l3 l l6 l8 19 2O 21 22 (green aphids) 'Bean 2 3 0 O 3 0 0 O O 3 0 0 O O 3 2 0 Megoura viceae Broad (black aphids) Bean 2 3 0 0 0 3 O 0 O 0 3 O 0 O 0 3 2 3 0 Aedes aegypti (mosquito larvae) Water- 1 0 O O O 0 0 3 2 0 3 0 O O 0 3 0 3 Aedes aegypti (mosquito adults) Plywood l 2 O O 0 0 0 0 2 0 0 O O 0 0 3 0 0 0 Musca domestica Milk/ (houseflies .Sugar 2 0 0 0 0 O O 3 O 0 2 0 2 O 3 O O 2 contact test) Pieris brassicae (cabbage \vhite Cabbage 2 0 0 0 3 O O O O O O 3 O 0 2 O 0 O caterpillars) A A A A A A A Plutella maculipennis Mustard/ 7 (diamond back moth paper 2 0 0 0 l 0 3 0 0 0 0 O 0 0 3 l larvae) A A A A A A A Phaedon cochleariae Mustard/ (mustard beetles) paper 2 0 O 0 0 0 0 l 0 0 0 0 2 0 O O O O O i A A A A Meloidogyne incognita (nematodes) Water 1 2 2 2 0 2 0 2 *In the contact test the flies are sprayed directly; in the residual test the flies are placed on a medium that has previously been treated.

Compounds Nos. l,4,5,7,8,9,l() and 13 gave rise to A weighed sample of the compound under test was abnormal growth effects in the larva of mosquitos dissolved in 0.5 cc of an ethanol and acetone mixture (Aedes aegyptz) Table 7 below gives the results of the tests carried out on further compounds listed in Table 1.

:50 v/v). The solution was diluted with 0.5 cc water and poured onto a calf feeding pellet in a glass Petri dish. The pellet was then air dried for 24 hours. The

TABLE 7 No. 3 Support of 7 No. of Compound (Table 1) Pest Species medium days 24 25 27 28 29 3O 32 33 34 3 8 40 41 42 43 44 46 Tetranychus telarius French (red spider mites, Bean 3 3 O 3 3 3 3 3 3 3 3 3 3 3 3 3 2 adults) Tetranychus telarius French I I (red spider mites, Bean 3 0 2 3 V 3 0 3 3 3 3 3 3 3 3 3 0 eggs) Aphis fabae Broad (green aphids) bean 2 O 0 3 3 3 0 3 0 3 O 3 O 3 3 O O Megoura viceae Broad (black aphids) Bean 2 0 0 3 3 3 0 0 0 0 0 3 0 3 3 0 0 Aedes aegypti I (mosquito larvae) Water l 3 3 3 3 3 3 3 O 3 3 3 3 3 3 3 3 Aedes aegypti (mosquito adults) Plywood l 0 O 2 3 O 2 2 2 O O O O 0 0 O 0 Musca domestica Milk/ (houseflies, sugar 2 l O 3 3 O 0 0 3 2 3 3 3 0 contact test*) Pieris brassicae (cabbage white caterpillars) Cabbage 2 O 3 O 3 O 3 3 3 0 3 0 0 3 3 3 O Plutella maculipennis Mustard/ (diamond back moth paper 2 0 O 0 3 0 l 2 l 2 0 0 l 0 2 0 O larvae) Phaedon cochleariae Mustard/ (mustard beetles) paper 2 O 2 O 3 O O O O O O 2 2 O O 0 O Meloidogyne incognita (nematodes) Water I 0 3 O 3 O In the contact test the flies were sprayed with the solution of the compound under testv EXAMPLE 4 weight of compound used was chosen so that the dried pellet contained 4% by weight of the active ingredient. Two replicates each consisting of a plastic Petri dish containing a pellet, 2 slugs, and a moistened filter paper This Example illustrates the molluscicidal activity of compounds used as active ingredients in the compositions of the invention. V

to maintain a high relative humidity were used in each test. The dishes were left in a cold room (10C.) After 6 days the kill was assessed.

The slugs used were Agriblimii-Jt reticulatus (Mull), and they had been starved for 24 hours before the commencement of the tests. The results of the test are set out in Table 8 below.

TABLE 10 No. of Application Preor Compound rate.pounds/ Post Plant Species (Table 1) acre emergence test b Ka Ca Pea On Bar Ri Oat 1 PFC 0 2 0 0 3 2 5 PIE 5 5 5 3 5 5 5 5 5 1 post 5 5 5 4 3 3 0 3 5 Post 5 5 5 4 5 3 0 4 5 Pre O l l 3 O 3 0 5 Post 3 3 2 o 2 0 0 0 l2 5 Post 5 5 5 1 0 2 0 0 5 Pre 4 4 4 3 0 19 5 Post 2 3 0 0 1 2 2 0 TABLE 8 An application rate of 1 pound per acre is equivalent cumpound No. Km of Slugs to 1.12 kilograms per hectare, and 5 pounds per acre is 4 100 equivalent to 5.6 kllograms per hectare. 3 100 The abbreviations used in Table 10 have the follow- 12 50 in meanin s: 15 5o g g 16 50 18 50 Abbreviation Full Name 50 Sb Sugar beet 27 100 K21 Kale 29 50 Ca Carrot 30 lOO 25 On Onion 32 100 Bar Barley 34 100 R1 Rice 42 50 43 100 This Example illustrates the herbicidal properties of the compounds of the present invention. The compounds were 'ball-milled in water containing a surfaceactive agent sold under the name of Lissapol and comprising a condensate of p-nonylphenol with seven to eight molar proportions of ethylene oxide. The ballmilled material was diluted with water to give a spray composition containing 0.1 of the surface-active agent, and sprayed on to young pot plants of the species listed in Table 9 below (Post-emergence test). The rate of application of the active ingredient was equivalent to 10 pounds per acre (11.2 kilograms per hectare) and the spray volume 100 gallons per acre (1 123 liters per hectare). Damage to the plants was assessed on a scale of 0 to 3 where 0 represents no effect and 3 represents complete kill. In the same experiment pots of soil were sown with seeds of the plant species listed in Table 9 and then sprayed with the above spray composition at the rate of 10 pounds per acre of active ingredient (pre-emergence test). The results are given in Table 9 below.

In a further test, the spray compositions prepared as described above were sprayed on to afurther group of plant species, at various rates of application. In this test the damage to the plants was assessed on a scale of 0 to 5 where 0 represents no effect and 5 represents complete kill. The results are given in Table 10 below.

This Example illustrates the herbicidal activity of further compounds used as active ingredients in the compositions of the invention. The compounds were tested on lettuce, tomato, wheat and maize plants as described in Example 5 except that the compounds were applied at 10 kilograms per hectare in a spray volume of 1000 liters per hectare, instead of 10 lb. per acre in gallons per acre. The results are given in Table 11 below.

TABLE 1 1 No. of Compound Pre-em'ergence (Table l) Lettuce To- Wheat Maize mato Nuwwuwuuwwm "U o u-uuauanutnwww OOM-OW-OOOO st-eme ence TABLE 12 Compound No. Application Preor Plant Species (Table l Postemergence test rate, kg/ hectare Pea On Bar 27 Pre Pre Post Pre Post Pre Post Pre Post Pre Post Pre Post mount EXAMPLE 7 This Example illustrates the selective herbicidal activity of compounds No. and 12 of Table 1. The compounds, formulated as in Example 5 were sprayed on to pots of soil previously sown with seeds of the plant species shown in Tables 13 and 14. The results for compound 5 are shown in Table 13. These results are assessments of the damage to the plants 28 days after treatment, on a scale of 0 to where O is no effect and 10 is complete kill.

-continued Common name Botanical name ssp. inodorum Redshank Polygonum persicaria White mustard Sinapis alba Wild oat Avenua fatua Speedwell Veronic spp EXAMPLE 8 This Example illustrates the preparation of 3,5- dichloro-2,6-difluoro-4(4-nitro-2-trifluoromethylanilinopyridine (compound No. 5 of Table 1).

Sodium hydride (2.4 g. of a dispersion in oil) Table 14 gives the results for compound No. 12 of Table 1. The figures are assessments of damage to the plants 23 days after treatment, on a scale of O to 5 where O is no effect and 5 is complete kill It will be seen from Tables 13 and 14 that compounds 5 and 12 caused damage to the broadleaved plants, while wheat and barley were undamaged.

The botanical names of the plants used were as follows:

Common name Botanical name Annual Nettle Urtica urens Chickweed Stellaria media Corn marigold Chrysanthemum segetum Groundsel Senecio vulgaris Knotgrass Polygonum aviculare Mayweed Tripleurospermum maritimum was washed with anhydrous petroleum ether, suspended in dry dimethyl-formamide (20 ml.) and cooled in ice. 2-Amino-5-nitrotrifluordmethyl-benzene (5.15 g.) in dimethyl formamide (10 ml.) was added dropwise to the stirred suspensionwhile the temperature was kept below 10C. 3,5 Dichlorotrifluoropyridine (5.05 g.) in dimethyl formamide (5 ml.) was then added dropwise, keeping the temperature below 10C. The mixture was allowed to warm to room temperature and stirred for 3 hours, thenpoured into ice (200 g.) The mixture was acidified and extracted with ether (2 X ml.) The ether extracts were washed with water (2 X 50 ml.) and dried over magnesium sulphate. The residue after removal of the ether was recrystallised three times from carbon tetrachloride, giving the product as a pale yellow solid (2.92 g.) of melting point 117C.

EXAMPLE 9 This Example illustrates the preparation of 3,5- dichloro-2,6-difluoro-4 2,4-dinitroanilinopyridine (compound No. 1 of Table 1).

Sodium hydride (2.4 g. of a 50% dispersion in oil) was washed with anhydrous petroleum ether and suspended in dry dimethylforrnamide (15 ml.) kept under an atmosphere of dry nitrogen. 4-Amino-3,5-dichloro- 2,6-difluoropyridine (4.9 g.) in dry dimethylformamide (20 ml.) was added dropwise to the suspension which was stirred and kept at less than C. A solution of 1chloro-2,4-dinitrobenzene (5.1 g.) in dry dimethyl formamide ml.) was then slowly added keeping the temperature below 10C. with stirring. The mixture was stirred for 3 hours, poured on to ice (200 g.) and acidified. The mixture was extracted with ether and the ether extracts washed three times with water (3 X 50 ml.) The residue from evaporation of the ether extract was extracted with boiling cyclohexane. The residue was taken up again in ether, washed again with water (2 X 50 ml. and the ether solution dried and evaporated. The residue was combined with the residue obtained by evaporation of the cyclohexane extract and recrystallised from carbon tetrachloride giving a yellow product (3.2 g.) of melting point 1 16C.

EXAMPLE 10 Following the method of Example 8 the following compounds listed in Table 1 were prepared from the reactants stated. The number given after each compound is its number in Table 1.

4-Anilino-3,5-dichloro-2,6-difluoropyridine (No. 2)

from 3,5-dichlorotrifluoropyridine and aniline.

3,5-Dichloro-2,6-difluoro-4(2,6-dichloroanilino)- pyridine (No. 3) from 3,S-dichlorotrifluoropyridine and 2,6-dichloroaniline.

3,5-Dichloro-2,6-difluoro-4(p-fluoroanilino)pyridine (No. 4) from 3,5-dichloro-2,4,6-trifluoropyridine and p-fluoroanilino.

3 ,5-Dichlo ro-2,6-difluoro-4( 2 ,4,6-trichloroanilino pyridine (No. 7) from 3,5-dichlorotrifluoropyridine and 2,4,6-trichloroaniline.

3,5-Dichloro-2,6-difluoro-4(pentachloroanilino)- pyridine (No. 9) from 3,S-dichlorotrifluoropyridine and pentachloroaniline.

3,5-Dichloro-2,6-difluoro-4(pentafluoroanilino)pyridine (No. 10) from 3,5-dichlorotrifluoropyradine and pentafluoroaniline.

3,5-Dichloro-2,6-difiuoro-4(2-nitroanilino)pyridine (No. 11) from 3,5-dichlorotrifluoropyridine and 2-nitroaniline.

3 ,5 -Dichlo ro-.2,6-difluoro-4( 2bromo-5 -trifiuoromethylanilino)pyridine (No. 13) from 3,5-dichlorotrifluoropyridine and 2-bromo-5-trifluoromethylaniline.

3,5-Dichloro-2,6-difluoro-4-(4-nitroanilino)pyridine (No. 14) from 3,5-dichlorotrifluoropyridine and 4nitroaniline.

3 ,5-Dichloro-2,6-difluoro-4( 2-nitro-4-trifluoromethylanilino) pyridine (No. 16) from 3,5-dichlorotrifluoropyridine and 2-nitro-4-trifluoromethylaniline.

3 ,5-Dichloro-2,6-difluoro-4( 3-trifluoromethylanilino)pyridine (No. 17) from 3,5-dichlorotrifluoropyridine and 3-trifiuoromethylaniline.

3,5-Dichloro-2,6-difluoro-4-(4-methoxy-2- nitroanilino)pyridine (No. 18) from 3,5-dichlorotrifluoropyridine and 4-methoxy-2-nitroaniline.

4(4-Cyano-2,3,5,6tetrafluoroanilino)-3,5-dichloro- 2,6-difluoropyridine (No. 19) from 3,5-dichlorotrifluoropyridine and 4-cyano-2,3,5,6-tetrafiuoroaniline.

, 3,S-Dichloro-2,6-difluoro-4(2,5-dichlor0-4-nitroanilino)pyridine (No. 24) from 3,5-dichloro trifluoropyridine and 2,5-dichloro-4-nitroaniline.

3,S-Dichlor0-2,6-difluoro-4-2,6-dichloro-4- nitroanilino)pyridine (No. 27) from 3,5-dichlorotrifluoropyridine and 2,6-dich1oro-4-nitroaniline.

4-( 4-Nitro-2-trifluoromethylanilino )-tetrafluoropyridine (No. 28) from pentafluoropyridine and 4- nitro-2-trifiuoromethylaniline.

3,5-Dichloro-2,6-difluoro-4(4-chloro-2,6-dinitroanilino)pyridine (No. 29) from 3,5-dich1orotrifluoropyridine and 4-chloro-2,6-dinitroaniline.

3,5-Dichloro-2,6-difluoro-4(2,5-dichlor-4-N,N-

dimethylsulphamoylanilino)pyridine (No. 3 1) from 3,5-dichlorotrifluoropyridine and 2,5- dichloro-4-N,N-dimethylsulphamoylaniline. 3-Chl0ro-4(4-nitro-2-trifiuoromethylanilino)-2,5,6-

trifluoropyridine (No. 32) from 3-chlorotetrafluoropyridine and 4-nitro-2-trifiuoromethylaniline. 3,S-Dichloro-2,6-difluoro-4(4-nitro-3-trifluoromethylanilino)pyridine (No. 36)from 3,5-dichlorotrifluoropyridine and 4-nitro-3-trifluoromethylaniline. 3-Chloro-4(2,4-dinitroanilino)-2,5,6-trifluoropyridine (No. 38) from 3-chlorotetrofluoropyridine and 2,4-dinitroaniline. 4(2-Bromo-4,6-dinitroanilino)-3,5-dichloro-2,6-

difluoropyridine (No. 40) from 3,5-dichlorotrifluoropyridine and 2bromo-4,6-dinitroaniline. 4(4-Nitro-2-trifluoromethylanilino)-tetrachloropyridine (No. 41) from pentachloropyridine and 4- nitro-2-trifiuoromethylaniline. 2-Fluoro-(4-nitro-2-trifluoromethylanilino)3,5,6-trichlorpyridine (No. 44) from 2,4-difluorotrichloropyridine and 4-nitro-2-trifluoromethylaniline. 2-Fluoro-3,4,5-trichlor-2(4-nitro-2-trifluoromethylanilino)pyridine (No. 47) from 2,6-difluoro- 3,4,5-trichloropyridine and 4-nitro-2-trifiuoromethylaniline. 2-Fluoro-3,5,6-tribromo-4(4-nitro-2-trifluoromethylanilino) pyridine (No. 48) from 2,4-difluoro- 3,5,6-tribromopyridine and 4-nitro-2-trifluoromethylaniline. 3,5-Dibromo-2,6-difluoro-4(4-nitro-2-trifluoromethyl anilino) pyridine (No. 49) from 3,5- dibromotrifluoropyridine and 4-nitro-2-trifluoromethylaniline. 3,S-Dichloro-2,6-difluoro-4(2-bromo-4- nitroanilino)pyridine (No. 50) from 3,5-dichlorotrifluoropyridine and 2-bromo-4-nitroaniline.

3 ,5 -Dichloro-2,6-difluoro-4( 2-methyl-4- nitroanilino)pyridine (No. 51) from 3,5-dichlorotrifluoropyridine and 2-methyl-4-nitroaniline.

The halogenated pyridines used in the preparation of the foregoing compounds have been described in the literature, except for the bromofluoro compounds. The bromofluoropyridines may be prepared by vapour phase bromination of appropriate fluoropyridines. Thus, 2-4-difluorotribromopyridine can be prepared by vapour phase bromination of 2,4-difluoropyridine and 3,S-dibromotrifluoropyridine by similar bromination of 2,4,6-trif1uoropyridine.

Following the method of Example 9 the following compounds listed in Table 1 were prepared from the reactants stated:

3,5-Dichloro-2,6-difluoro4(2,4-dinitro-5- fluoroanilino)pyridine (No. 6) from 4-amino-3,5- dichloro-2,6-difluoropyridine and 1.5-difluoro-2,4- dinitrobenzene.

Tetrachloro-4(2,4-dinitroanilino)pyridine (No. 8)

thylamino) pyridine (No. 25) from 4-amino-3,5-

dichloro-2,6-difluoropyridine and 2,4-dinitro-lchloronaphthalene.

4( 2-Cyano-4-nitroanilino )-3 ,5 -dichloro-2,6-

difluoropyridine (No. 26) from 4-amino-3,5- dichloro-2,6-difluoropyridine and 2-cyano-4-nitrochlorobenzene.

4(4-Bromo-2,3,5,6-tetrafluoroanilino)-3,5-dichloro- 2,6-difluoropyridine (No. 30) from 4-amino-3,5- dichloro-2,6-difluoropyridine and pentafluorobromobenzene.

3 ,5-Dichloro-4( 3 ,4-dicyano-2,5 ,6-trifluoroanilino) 2,6-difluoropyridine (No. 33) from 4-amino-3,5- dichloro-Z,6-difluoropyridine and 1,2-dicyano-tetrafluorobenzene.

4(4-Cyano-2,6-dinitroanilino)-3,5-dichl ro-2,6-

difluoroypridine (No. 34) from 4-amino.-3,5- dichloro-2,6-difluoropyridine and 4-cyano-2,6- dinitrochlorobenzene.

4(5-Fluoro12,4-Fluoro-(No. 35) from 4-arninotetrachloropyridine and l,S-difluoro-Z,4-dinitrobenzene.

Tetrafluoro4( 2,4,6-trinitroanilino )pyridine (No.

37) from 4-amino-tetrafluoropyridine and 2,4,6- trinitrochlorobenzene.

4(2,4-Dinitro-5-fluoroanilinotetrafluoropyridine (No. 39) from 4-aminotetrafluoropyridine and l ,3-difluoro-4,6-dinitrobenzene.

4(4-Cyano-2,3,5,6-tetrafluoroanilino)tetrachloropyridine (No. 42) from 4-aminotetrachloropyridine and pentafluorocyanobenzene.

3,5-Dichloro 2,6-difluoro-4(3,5-difluoro-2,4,6-trichloroanilino) pyridine (No. 43) from 4-amino- 3,5-dichloro-2,6-difluoropyridine and 1,3,5-trichloro-Z,4,6-trifluorobenzene.

EXAMPLE 1 1 This Example illustrates the preparation of compound 46 of Table l, 3,5-Dichloro-4(4-cyano-2,3,5,6- tetrafluoroanilino)-2-fluoro-6-methoxypyridine (3 .0 g.) in ether ml.) was treated with methyl isocyanate (0.7 g.) N-methylmorpholine (3 drops) was added and the solution was allowed to stand at room temperature for 1 week. The white solid which separated was recrystallised from methylene dichloride/petroleum ether (bp 40 60C.) to give the product (3.3 g.)

26 Compound No. 45 of Table 1 was prepared in a similar way using 3,5-dichloro-2,6-difluoro-4-(4-nitro-tetrafluoroanilino) pyridine and methyl isocyanate.

EXAMPLE 12 This Example illustrates a composition according to invention which comprises a concentrate comprising a miscible oil which is readily convertible by dilution with water into a liquid preparation suitable for spraying purposes.

The concentrate has the following compositions:

7: wt. Compound No. l of Table 1 25.0 LUBROL L (Alkylphenol/ethylene oxide condensate; Lubrol is a Trade Mark) 2.5

Calcium dodecylbenzenesulphonate 2.5

AROMASOL H (alkylbenzene solvent Aromasol is a Trade Mark) 70.0

EXAMPLE 13 This Example also illustrates a concentrate which is in the form of a miscible oil. The composition of this concentrate is as follows:

Compound No. 2 of Table 1 25.0 'LUBROL L (Lubrol is a Trade Mark) 4.0 Calcium dodecylbenzenesulphonate 6 .0 AROMASOL H (Aromasol' is a Trade Mark) 65.0

EXAMPLE 14 This Example illustrates a wettable powder having the following composition:

Compound No. 3 of Table I 25.0 Sodium silicate 50 Calcium lignosulphonate 50 China clay 65.0

EXAMPLE 15 This Example illustrates an atomisable fluid comprising a mixture consisting of 25% by weight of the compound No. 4 of Table 1 and by weight of xylene.

EXAMPLE 16 This'Example illustrates a dusting powder which may be applied directly to plants or other surfaces and comprises 1% by weight of compound No. 5 of Table 1 and 99% by weight of talc.

EXAMPLE 17 25 Parts by weight of compound No. 6 of Table 1, 65 parts by weight of xylene, and 10 parts of an alkyl aryl polyether alcohol Triton X-100 (Triton is a Trade Mark) were mixed There was thus obtained an emulsifiable concentrate which can be mixed with water to produce an emulsion suitable for use in agricultural applications.

EXAMPLE 1s 5 Parts by weight of compound No. 7 of Table l were thoroughly mixed with 95 parts by weight of talc. There was thus obtained a dusting powder.

. EXAMPLE l9 10 Parts by weight of compound No. 19 of Table 1, 10 parts of an ethylene oxide octylphenol condensate. (Lissapol NX;-Lissapol is a Trade Mark) and 80 parts by weight of diacetone alcohol were thoroughly mixed. There was thus-obtained a concentrate which, on mixing with water, gave an aqueous dispersion suitable for application as a spray in the control of insect pests.

EXAMPLE 2O This Example illustrates a concentrated liquid formulation in the form of an emulsion. The ingredients listed below were mixed together in the stated proportions and the whole stirred until the constituents were dissolved.

Compound No. l of Table 1 2O -LUBROL' L (Lubrol is a Trade Mark) 17 Calcium dodecylbenzenesulphonate 3 Ethylene dichloride 45 Aromasol' H (Aromasol is a Trade Mark) l5 EXAMPLE 21 The ingredients listed below were ground together in the proportions stated to produce a powdered mixture readily dispersible in liquids.

Compound No. l of Table l 50 Dispersol T 5 China clay 45 EXAMPLE 22 Compound No. 2 of Table 1 5O Dispersol T 12.5 Goulac 5 Calcium dodecylbenzenesulphonate 12.5 Sodium acetate EXAMPLE 23 A granular composition was prepared'by dissolving the active ingredient in acetone, spraying the solution obtained onto granules of pumice and allowing the solvent to evaporate.

An aqueous dispersion formulation was prepared by mixing and grinding the ingredients recited below in the proportions stated.

Compound No. 3 of Table l 40 Calcium lignosulphonate 10 Water 50 EXAMPLE 25 This Example illustrates the activity of compounds used as the active ingredients of compositions according to the invention against a variety of plant bacterial diseases and fungal post-harvest saprophytic diseases. In a test for such activity, 5 milligrams of the compound to be tested was dissolved or suspended in 10 ml. of acetone and enough of this solution or suspension was added to 18 ml. of nutrient agar (for the bacterial diseases) or 16 ml. of 2% malt agar (for the fungal diseases) to give a final concentration of 50 parts per million of the compound under test. A streptomycin preparation (2 ml. containing 100 units per ml.) was added to the malt agar to prevent bacterial contamination of the fungal tests.

The agar preparations were dried overnight in Petri dishes and inoculated the following morning with the bacterial or fungal diseases using a multipoint inoculator. The antibacterial activity was assessed after 5 days and the antifungal activity after 6 days. The results of the tests are set out in Table 16 (anti bacterial activity) and Table 17 (antifungal activity). The results are graded as in Example 1 above. The names of the dis- TABLE 16 Compound No. Disease Code (Table l) Table 1 Bl B2 B3 B4 B5 B6 B7 B8 B9 B10 l 3 3 3 3 3 3 3 3 3 3 6 3 3 3 l 2 2 l l 0 1 l5 3 3 3 3 3 3 3 3 3 3 l9 3 3 3 3 3 3 3 3 3 3 2O 0 3 3 2 l 2 2 0 0 0 2l 2 3 3 3 2 3 3 l 2 3 24 3 3 3 3 3 3 3 2 3 2 29 3 3 3 3 3 3 3 3 3 3 33 3 3 3 3 3 3 3 0 0 3 34 0 3 2 0 2 3 3 O 0 l 35 O O O 0 l 2 2 0 0 2 40 2 2 3 l 2 l 2 l l 2 4l 3 0 2 l l l 0 0 3 2 44 3 3 3 3 3 3 3 3 3 3 TABLE 17 Corn.

No. Disease Code (Table Table 1 Fl F2 F3 F4 F5 F6 F7 F8 F9 FlO F11 F12 EXAMPLE 26 This Example illustrates the insecticidal activity of compounds used as active ingredients of the compositions of the invention. The compounds were submitted to a test in which a solution of the compound was applied to a filter paper upon which larvae of the blowfly (Lucilia serrata) were maintained. The filter paper upon which the blowfly larvae were kept was impregnated with horse serum. The toxic effects produced by the compounds used in the compositions of the invention were assessed by comparison with the effects of known insecticides. The results were expressed on a scale of 1 to 6 in which 5 represents insecticidal activity equal to that of the known insecticide and 6 represents activity 10 times that of the standard. The results are given below in Table 18.

TABLE 18 Activity relative to Compound No. lindane LUBROL L is a condensate of 1 mole of nonyl phenol with 13 molar proportions of ethylene oxide.

is a solvent mixture of alkylbenzenes. is a mixture of sodium sulphate and a condensate of formaldehyde with the sodium salt of naphthalene sulphonic AROMASOL H DISPERSOL T a LUBROL APN 5 is a condensate of 1 mole of nonyl phenol with 5 /11 moles of naphthalene oxide. is a sodium carboxymethyl cellulose thickener. is a condensate of 1 mole of nonyl phenol with 8 moles of ethylene oxide.

CELLOFAS B 600 LISSAPOL' NX We claim:

1. A method of inhibiting the growth of unwanted vegetation, which comprises applying to the locus of the vegetation a herbicidally effective amoung of a 4-arylaminopyridine of the formula:

or a salt thereof, wherein R is hydrogen; Ar is phenyl, or substituted phenyl bearing a substituent selected from the group consisting of chlorine, bromine, fluorine, nitro, cyano, alkyl of 1-4 carbons and trifiuoromethyl, X is selected from the group consisting of chlorine, bromine and fluorine; and n is 3 or 4.

2. A method according to claim 1 wherein n is 4; X is selected from the group consisting of chlorine and bromine.

3. A method according to claim 1 in which the rate of application of the arylaminopyridine is from 0.22 to l 1.2 kilograms per hectare. 

1. A METHOD OF INHIBITING THE GROWTH OF UNWANTED VEGETATION, WHICH COMPRISES APPLYING TO THE LOCUS OF THE VEGETATION A HERBICIDALLY EFFECTIVE AMOUNG OF A 4-ARYLAMINOPYRIDINE THE FORMULA:
 2. A method according to claim 1 wherein n is 4; X is selected from the group consisting of chlorine and bromine.
 3. A method according to claim 1 in which the rate of application of the arylaminopyridine is from 0.22 to 11.2 kilograms per hectare. 